c_white = Color.new (31, 31, 31)
c_red = Color.new (31, 0, 0)
c_green = Color.new (0, 31, 0)
c_blue = Color.new (0, 0, 31)
c_blue2 = Color.new (0, 0, 15)
c_black = Color.new (0, 0, 0)
c_yellow = Color.new (31, 31, 0)
c_pink = Color.new (31, 0, 31)
c_lightblue = Color.new (0, 31, 31)
----------------------------------------------
function Color.new2 (r, g, b)
  r = math.floor(r*31/255)
  g = math.floor(g*31/255)
  b = math.floor(b*31/255)
  return Color.new (r, g, b)
end
----------------------------------------------
c_grey = Color.new2 (128, 128, 128)
c_wingrey = Color.new2 (240, 240, 240)
c_lightgrey = Color.new2 (192, 192, 192)
c_orange = Color.new2 (255, 127, 39)
c_salmon = Color.new2 (255, 128, 128)
c_khaki = Color.new2 (0, 128, 0)
c_lightgreen = Color.new2 (128, 255, 0)
c_bluesky = Color.new2 (128, 255, 255)
c_lightpink = Color.new2 (255, 128, 255)
---to complete---

function Color.negate (r, g, b)
  return Color.new (31-r, 31-g, 31-b)
end

function Color.negate2 (r, g, b)
  return Color.new2 (255-r, 255-g, 255-b)
end
